A major goal of the neuroscience community is to develop treatment strategies that will slow or forestall the progression of chronic neurodegenerative diseases. Parkinson's disease (PD) is one of the most common adult neurodegenerative disorders, affecting over 1 million people in North America and the European Union, As a first step in identifying such therapies, the NINDS Exploratory Trials in Parkinson's disease (NET-PD) network successfully completed futility studies, which identified creatine as a potential agent to slow clinical decline in PD. The NET-PD network is now conducting a large, long-term, Phase 3 trial (known as LSI) comparing creatine to placebo. An additional futility study is underway (the FS-ZONE study) to examine the potential for pioglitazone as a disease modifying therapy in PD.